Question SMTP greeting

[hardbrasil]

hello fellas,

i had configured my Plesk with postfix and set "Outgoing mail mode" with "Send from domain IP addresses and use domain names in SMTP greeting"

when i run dnsstuff into my domain i got this:

WARNING: The hostname in the SMTP greeting does not match the reverse DNS (PTR) record for your mail server. This probably won't cause any harm, but may be a technical violation of

it was not suppose to work?

thanks

 

[IgorG]

What about this your old thread?

https://talk.plesk.com/threads/the-...eeting-does-not-match-the-reverse-dns.334802/

 

[hardbrasil]

Hi @IgorG
it's quite different because in this situation i have the main IP of the server working well. But when i set a fix IP to another domain i would like to have this domain FQNS too.
i am building this for email marketing proposes and i need to have all email complaints working well.

 

[Greg Sims]

Igor,

I am having the same issue here. Here is the definition of this setting in the help text:

Send from domain IP addresses and use domain names in SMTP greeting. If selected, Plesk changes the mail server configuration so that the SMTP greeting contains the name of the domain from which the email message is sent. Selecting this option may result in mail sent from some or all domains being marked as spam if the destination mail server uses cbl and more than one domain on the Plesk server uses the same IP address. In addition, selecting this option on Plesk servers hosting a large (more than 100) number of domains will likely result in significantly increased server load. This option works best if you have allocated a dedicated IP address to every domain hosted on the Plesk server, and the number of domains hosted on the server is not very large.

I tested the SMTP Greeting with the default setting: Send from domain IP addresses under CentOS 7. The email is sent from the domain IP address and the SMTP Greeting is the name of the Plesk Server hostname. This is all as expected.

When I changed the setting to: Send from domain IP addresses and use domain names in SMTP greeting, the behavior remains the same. The SMTP Greeting continues to be the hostname of the Plesk server. This causes a mismatch between the SMTP Greeting and the Reverse DNS of the IP Address from which the email was sent. This is flagged as an error in DNSSTUFF.

The only "Solution" to this problem seems to be making the Reverse DNS for ALL server IP Addresses match the hostname of the Plesk Server. This is not acceptable in many cases as clients want the SMTP greetings to match THEIR domain names (the client) -- not My (the provider) domain name which is part of the Plesk hostname. It seems that this is what the Send from domain IP addresses and use domain names in SMTP greeting, is designed to resolve. Do you agree that we have a bug here?

Thanks, Greg

 

[UFHH01]

The only "Solution" to this problem seems to be making the Reverse DNS for ALL server IP Addresses match the hostname of the Plesk Server. This is not acceptable in many cases as clients want the SMTP greetings to match THEIR domain names (the client) -- not My (the provider) domain name which is part of the Plesk hostname. It seems that this is what the Send from domain IP addresses and use domain names in SMTP greeting, is designed to resolve. Do you agree that we have a bug here?

I disagree here, that this could be considered to be a bug, because you have the option to modify your DNS - entry for "SPF", including the HOSTNAME of your server and the corresponding reverse IP. We use for example:

v=spf1 +a +mx +a:<hostname> +ip4:<ip.mail> ?all​

... in our DNS - templates, which results in domain - specific entries as for example:

v=spf1 +mx +a a:servername.serverFQDN ip4:XXX.XXX.XXX.XXX ?all​

With this DNS - configuration, you could still receive a WARNING ( no error ... just a warning! ) on configuration - checker - sites, but they will always state clear: "this MAY be a violation of RFC5321" ( which in fact isn't the case!!! ).
Corresponding eMail - server should never reject an eMail with this configuration, according to the standarts ( https://tools.ietf.org/html/rfc5321 ). ​

 

[Greg Sims]

My definition of a "Bug" is when the design (in this case the Help Text) does not match the implementation (what actually happens in Plesk).

When one changes from Send from domain IP addresses to Send from domain IP addresses and use domain names in SMTP greeting, what change in behavior should be seen? In my case, there is no change -- the SMTP Greeting remains the Plesk Server hostname. This does not seem to match the Help Text which says in part, "the SMTP greeting contains the name of the domain from which the email message is sent.". I would expect the SMTP Greeting to change. This is my question/issue/concern that there may be a bug. I would love to get some feedback on this.

Thanks again! Greg